Toy aeroplane



w" E. BACK TOY AEROPLANE Feb. 11, 1936.

Filed June 11', 1935 2 Sheets-Sheet l W. E. BACK Feb. 11, 1936.

TOY AERQPLANE Filed June 11, 1935 2 Sheets-Sheet 2 Patented Feb. 11, 1936 UNITED STATES PATENT OFFICE Application June 11, 1935, Serial No. 26,059 In Great Britain June 16, 1934 5 Claims.

This invention relates to toy aeroplane gliders and more particularly to such gliders which are devoid of mechanical contained power, whilst the objects of my invention are concerned with the mode of constructing and attaching the wings, or plane, and the directional controlling tail surfaces to a weighted body; to the mode of attaching dummy air screws or screw, landing buffer and landing wheels; to means for launching the machine, and provisions incorporated in the design and construction of same, calculated to provide against damage when contact is made with any heavy object during flight.

Wood is the principal material in the construction of these gliders; for the wing and tail unit surfaces, likewise the body, are generally built up with a combination of suitably light three ply sheet fibre or the like, and this lighter material is reinforced where necessary with wood or fibre ribs, beams, spars or the like, such being firmly glued or cemented, and nailed or screwed to same.

According to the present invention means are provided whereby the camber and angle of incidence of the wing or wings on either side of the glider body can be adjusted.

Preferably the wing or wings is or are pivotally attached to longitudinal supports formed on or secured to the glider body, whereby should one side of a wing strike a heavy object during flight, the wing will rotate or pivot to absorb the shock Without breakage.

Preferably also the wing or wings is or are elastically attached to the longitudinal supports the elastic attachment means acting as a shock absorber to prevent damage of the wing and to return said wing to its normal position after striking any heavy object.

Means may also be incorporated in the wing tip ends so as to lessen damage thereof should the glider crash.

Further features of a toy glider according to my invention will be observed when the drawings appended to this specification are described.

In the accompanying drawings there is illustrated by way of example one form of the invention as applied to a monoplane glider and also one form of a device for launching said glider. In said drawings:

Figure l is a plan view of the glider;

Figure 2 a longitudinal section, parts being shown in elevation,

Figure 3 a front elevation partly in section;

Figure 4 is a detail sectional view of a. wing taken on the line 4-4 Figure 1;

Figure 5 is a detail sectional view of the rear part of the glider body and Figure 6 represents a diagrammatic view of the launching device.

Referring now to Figures 1-5, the lifting surfaces or wings I are securely held at or near their centre of lift on to longitudinal supports 2 secured on either side of the glider body 3 by means of a pulling force exerted through suitable elastic medium or media so as to permit the wing to give in most directions relative to the body.

Should the gliders body be sufficiently wide, it may be preferable to fix or form the longitudinal supports 2 on the top of the body; or such supports could even be fixed to the centre section of the wing, and thus make contact with the lateral top edges of the body in such a manner as suitably to stabilize the wings contact to same.

In order to secure the wings in position, the longitudinal supports 2 are of such dimensions that their top surfaces are above the upper surface of the body 3 whilst the wings are provided with holes 4, corresponding holes 5 being provided in the body 3 through which holes pass elastic cords 6, the said cords being knotted at the top and being stretched round the bottom of the body and anchored thereto by any suitable means e. g. by pins or screws 1. The lower ends of the elastic cords 6 are provided with means e. g. a string or wire 8 for facilitating the fastening or unfastening of the cords. The holes 4 and 5 have their sharp edges carefully rounded off so as to cause no out or damage to the elastic cords 6 when such pass through and downwards to their respective anchorages under or adjacent the bottom of the body. In order more effectively to form the anchorage the wing is reinforced as shown at la, so as to obtain a greater frictional surface for contact between the wing and longitudinal support or glider body.

Thus it will be seen that should one side of a wing strike a heavy object during flight, causing a rotating movement to occur relative to the body, the elastic medium or media will stretch and pull against the direction of movement, and finally after absorbing the shock of impact, will quickly restore the wing to more or less its correct position, relative to the body.

If desired however the holes in the wings may register with holes provided in the longitudinal known means, e. g. swivelling gate pins, may be employed for locking the elastic cords 6 in such holes or recesses during flight.

Generally it will be found necessary to employ a metal weight 9 on the forward part of the body so as to counterbalance the weight of the tail unit and rear portion of the body.

The metal weight 9 is so formed as to constitute a bracket or clip for the attachment of a shock absorbing buffer I D to the extreme forward part of the body.

Such a buffer could be formed from a suitable piece of india-rubber hose pipe, the interior of such accommodating a part of the aforementioned metal clip or bracket 9, and also containing any suitable shock absorbing material, such as cork or sponge rubber II.

A groove is formed on the front of the body so as to accommodate the rubber buffer, and likewise a recess I2 could be also formed along the bottom portion of the body so as to position and help to hold the aforementioned metal weight or clip; which latter is held firmly by any suitable screw holding I3.

Landing skids I4 could be suitably formed from steel piano wire, and the aforementioned weight and groove or recess could well be utilized for fixing same to the forward bottom part of the body.

Likewise such skids could have small landing wheels I5 on their rear ends.

A feature of these gliders, is the shape of a deep body, which is intended not only to impart stability in fiight (due to a low centre of gravity), but also to afford protection against damage to the vertical tail fin I6, which is firmly fixed into a saw cut or slot formed at the extreme end of the body.

To make this more clear; the bottom portion of the deep body (which might in fact be a suitably shaped wood spar, extending the entire length and holding the vertical tail fin) has its length positioned in approximately the line of light, and thus the greatest proportion of the vertical fin I6 is situated below the wing or lifting surface I, and also behind the bulk of the body.

Likewise such a design of body is intended to permit a perceptible amount of lateral give or twist to the vertical fin, calculated to lessen the chance of fracture should it receive a side blow from the wing or lifting plane, when such has been caused violently to rotate upon the body, as previously described.

Secured to the body 3 at the rear thereof is a tail plane I! suitably strengthened by a rib Ila, the whole of which tail plane is situated below the tail fin I6. The method of securing the tail plane I! is the same as that employed for the front wings i. e. the tail plane is secured by means of an elastic cord I8, so as to be capable of pivoting or giving should the glider crash thereby minimizing the risk of damaging the said tail plane.

Both the vertical fin and tail plane could be stamped out in a press to the desired shape from a sheet of thin ply wood, fibre, or any such suitable material; but the fin does not extend below the bottom surface of the body; for it is at this position that the tail plane is held through an elastic medium or media, and has freedom to rotate or move in most directions.

Referring now to the construction of the wing or main lifting surface I as illustrated in Figures 1 and 4, the entire shape and area may be cut or pressed out from a sheet of thin ply wood, fibre, or any such suitable material, and is glued or suitably fixed to a single strengthening spar I9 which extends laterally from tip to tip, and is positioned along the forward and underneath portion of same.

The single spar could be made from a suitably thin wood lath (lightened by hollowing out if necessary) the width extending from a position at or near the normal centre of lift of the wing, to the forward edge of same.

The rear portion of the spar I9 is preferably chamfered as shown so as to impart a normal flow of air, and hence imitate the natural camber, to the underside of the wing.

The wing is preferably strengthened on its under surface by a number of thin spars 20 (corresponding to the number of ribs mentioned below) to enable the wing to have secured thereto ribs 2| e. g. by pins or rivets 22, the ribs ZI being so formed as to impart to the finished wing at suitable camber, the said ribs 2| being positioned along the top surface of the wing and extending in the line of flight from the entering edge to the trailing edge of the wing.

These ribs could be suitably made from wood, or pressed out from sheet fibre, or be a celluloid (or similar substance) casting, and any suitable method for firmly gluing or cementing such to the wing could be used. The ribs 2I immediately adjacent the glider body are preferably interconnected as shown at 2 la. so as to strengthen the trailing edge of the lifting surface.

Provision can be made for rectifying faulty inherent lateral balance of these toy gliders, by causing a deeper camber and larger angle of incidence to the side of the wing which has a tendency to fall.

The method intended to effect this is as follovws:

The rib or ribs 2| situated at the lateral ends of the wing I are not glued or cemented entirely to the wing, but have a free portion 24 at the trailing edge of same, as to permit of any suitable small ring of elastic material or wedge 23 to be inserted between the top surface of wing, and under portion of rib respectively.

The ring or wedge could be attached by a thread to the wing, adjacent to the point required; or a small metal screw (having its point removed) could be screwed downwards through that part of the unglued rib, as to force the trailing edge of the wing surface downwards, and thus effect a deeper camber and greater angle of incidence.

The forward edge of the aforementioned wood lath or the like, (constituting the spar and strength of a wing), is provided with a rounded groove along its entire length, for the purpose of positioning a shock absorbing material 25 such as cork or soft india-rubber, which is preferably of a round section, as it constitutes the entering edge of the wing when firmly glued or cemented into the groove. Glued or adhesive tape could be wrapped around the shock absorbing material from the underneath of the spar to the top of the wing, and by such a means it is intended to prevent damage should contact be made with a heavy object during flight.

The breadth of the aforementioned spar decreases gradually towards the wing tip ends, as also does the chord of the wing at this particular part: for the trailing edge is swept forward to meet the spar, causing the plan of the wing to have tapered ends.

My reason for thus shaping the wing ends, is

to :lessen the risk of fracture should the glider side'slip to the ground. I

Intended also as an added protection in such an revent, the india-rubber entering edge could be-suitably wrapped around the spar ends, or

could have a small length protruding beyond the wing-ends as'clearly shown in Figure l.

Adummy-air screw, or screws 26 which revolvezinthe air stream, are preferably fitted to any-part of the body or wing; and so that such will not-be damaged by contact with a heavy object during flight, it or they are provided with a-flexible axle or spindle, suitably formed from a'thin gauge steel piano wire, so as to enable them to give in all directions.

The air screws could be made from any suitable material and are shaped differently to those generally; employed on other aeroplane toys; in that the blades have a very coarse pitch, in-

zoiytended: to cause little wind resistance. The body 31 0f the glider may if desired be hollowed out for the purpose of lightening the device and also to provideextra buoyancy should the glider fall on tozwater. Such an arrangement is shown more particularly in Figure 5 in which the rear part of-thebody is formed of two pieces of wood lb, Ic, interconnected for strengthening purposes by cross pieces Id, the upper part of the body being covered over by a fabric or like sheet le. The glider has its initial impetus for flight imparted to it by the stretching and release of an elastic medium or media, which latter is provided with a loop as to engage with a pin, hook or the like 21 situated or formed on the underneath and forward part of the body, and of such a shape as to freely disengage when the elastic has spent its impulsive influence.

A simple type of such hook could be fashioned from a suitable piece of steel piano wire, which could clip on to the aforementioned rubber buffer, and in such a manner that any shock on same from contact with a stone or hard mass when landing after a flight, would be transmitted to and absorbed by the buffer itself.

I intend the wings to easily be detachable for packing purposes, and this is simply effected by disengaging the elastic holding the wing to body, from any known, or simple type of anchorage.

Suitable markings can be provided on the wings or lifting plane and tail plane for correctly positioning them relative to the body.

As an essential part of this toy is the provision of a launching device, capable of being contained complete in the same packing box as that containing the glider, which launching device is illustrated diagrammatically in Figure 6. Such a launching device consists of one or more wood or metal rods 28 or the like of suitable length and thickness, which when there are more than one, are capable of being jointed together (much like a fishing rod) into one long rod. On the topmost portion ofthis long, or single rod, are anchored two or more stay cords or wires 29 of a suitable length, and having a wood or metal peg 30 attached to their respective ends, for pushing or driving into the ground. Such pegs could in reality be a strong meat skewer or a heavy wire nail or the like.

The aforementioned stay cords with their anchor pegs are intended to hold the long or single rod in a more or less upright position, and to the top of such is anchored the necessary length of elastic 3| for launching the glider.

A coloured flag 32 made from any suitable light material could be fitted to the top portion of the rod, as to show the direction of wind.

Each stay cord or wire is provided and attached to a suitably shaped piece of net wood 33, or

anything that would serve the double purpose of acting as a spool for winding up the loose cordor wire when packing away in the box, and als'o for acting as anchoragesin conjunction with the pegs, by their burial in loose sandysoil, should the nature of the flying field be such.

It is to be understood that in the appended claims no claim is made to this launching device per se, but only for the device when used with the glider as described and claimed in this specification.

Silk or cotton covered elastic will generallybe' used for launching gliders, as such'is not easyto over stretch and break.

Any portion of these toy aeroplane gliders that possibly might come into violent contact during flight with any heavy object, could be protectedprevent damage, but with larger typesof'these' toys, suitable steel plane wire wing tip skids= could be fitted as an added protection.

Provision could also be made for altering the setting of the tail plane relative to its body, as to cause the glider to be able to loop the loop. Such provision consists of an elastic ring 34 embracing the rear part of the body and which can be employed as a wedge to alter the angle of the tail plane.

This can be effected by any similar method as previously described for causing alteration of angle to the trailing edges of the wings.

In place of the loop of elastic medium or media engaging a pin or hook positioned on the forward part of a gliders body as previously described for launching purposes, the same result could be effected by attaching a suitable shaped hook fitting on to the end of the elastic for the purpose of engaging with a ring hole or shoulder positioned or formed at the forward end of the body.

With a glider having a large Wing span, the weight of the wing on either side of the glider body may cause the wing tips to droop. In order to overcome this defect, I may secure across the top of the ribs 2| any suitable strengthening member or members Zlb, e. g. a strip or strips of thin ply wood.

What I claim is:

l. A toy glider devoid of self contained mechanical power comprising a body, a longitudinal support carried by said body on each side thereof, at least one wing, elastic attachment means which pass through apertures in each wing and corresponding registering apertures in the glider body and camber and angle of incidence varying means in conjunction with at least one wing whereby the camber and angle of incidence of each wing can be adjusted, the pivotal attachment of said wings to said supports allow ing the wing to rotate or pivot on the support to absorb shock without breakage should one side of a wing strike any heavy object.

2. A toy glider devoid of self contained mechanical power comprising a body, at least one wing attached on either side of said body, a plurality of ribs secured on the upper surface of the wings, said ribs being curved to impart to said wing a desired camber, further ribs on said wings, which further ribs are not secured to the wing over the whole length of the rib, means adapted to engage with the free portion of said further ribs at the trailing edges thereof so as to adjust the trailing edge and hence the camber and angle of incidence of each wing surface.

3. A toy glider devoid of self contained mechanical power comprising a body, a longitudinal support carried by said body on each side thererib, means adapted to engage with the free portion of said further ribs at the trailing edges thereof so as to adjust the trailing edge and hence the camber and angle of incidence of each wing surface.

4. A toy glider devoid of self contained mechanical power comprising a body, at least one wing attached on either side of said body, a

strengthening spar extending over the whole wing span from a position adjacent the normal centre of lift of the wing to the forward edge thereof, which spar may be chamfered, whilst the lateral ends or tips of the wing proper taper and terminate acutely, a plurality of ribs secured on the upper surface of the wings, said ribs being curved to impart to said Wing at desired camber, further ribs on said wings which further ribs are not secured to the wing over the whole length of the rib, means adapted to engage with the free portion of said further ribs at the trailing edges thereof so as to adjust the trailing edge and hence the camber and angle of incidence of each wing surface.

5. A toy glider devoid of self contained mechanical power comprising a body, a tail fin fixed at its bottom portion to the rear of said body, a tail plane independent of said tail fin, elastic means for pivotally mounting said tail plane beneath said body, a longitudinal support carried by said body on each side thereof, at least one wing on either side of the glider body, elastic attachment means for pivotally attaching each wing to a longitudinal support, said elastic attachment means acting as a shock absorber and as means for returning said wing or wings to the normal position after striking any heavy object, and camber and angle of incidence varying means in conjunction with each wing.

WILLIAM EDWARD BACK. 

